198 research outputs found
Transportation Trends and Funding in South Africa
The funding of transportation, including both the road network and public transport, has become more of an issue than ever before. There is concern about the traditional method of road use taxation, namely the fuel levy, due to improved fuel consumption of vehicles and the potential phasing in of electric vehicles. Electronic tolling in Gauteng has been strongly opposed by motorists. The purpose of this paper is to present the latest available and relevant transportation trends, as well as to provide a perspective of the latest thinking wrt transportation funding, in an effort to contribute to the debate and possibly assist in getting some convergence in moving forward.
It is concluded that motorisation is growing rapidly, with the concurrent pressure on road travel. Whilst experts are suggesting new methods of road use taxation, through inter alia a distance based charge, it is clear that such a technique will be costly to administrate and likely to be resisted by many motorists. Research in this respect is clearly warranted.Papers presented at the 38th International Southern African Transport Conference on "Disruptive transport technologies - is South and Southern Africa ready?" held at CSIR International Convention Centre, Pretoria, South Africa on 8th to 11th July 2019
Perspectives on the future of personal transport in South Africa
Being a developing middle income country, South Africa has considerable transportation challenges. Car ownership and use are rising with improved economic conditions, but congestion on the road network is worsening all the time. Retaining public transport users is costing more in the form of operating and capital subsidies. The road safety situation is poor when compared to international benchmarks, and can be considered a national crisis. The purpose of this paper is to illustrate current trends and to provide some perspective on where South Africa could be heading with respect to these issues.Paper presented at the 35th Annual Southern African Transport Conference 4-7 July 2016 "Transport ? a catalyst for socio-economic
growth and development opportunities to improve quality of life", CSIR International Convention Centre, Pretoria, South Africa.The Minister of Transport, South AfricaTransportation Research Board of the US
Coulomb interaction between a spherical and a deformed nuclei
We present analytic expressions of the Coulomb interaction between a
spherical and a deformed nuclei which are valid for all separation distance. We
demonstrate their significant deviations from commonly used formulae in the
region inside the Coulomb radius, and show that they remove various
shortcomings of the conventional formulae.Comment: 7 pages 4 figure
Projection and ground state correlations made simple
We develop and test efficient approximations to estimate ground state
correlations associated with low- and zero-energy modes. The scheme is an
extension of the generator-coordinate-method (GCM) within Gaussian overlap
approximation (GOA). We show that GOA fails in non-Cartesian topologies and
present a topologically correct generalization of GOA (topGOA). An RPA-like
correction is derived as the small amplitude limit of topGOA, called topRPA.
Using exactly solvable models, the topGOA and topRPA schemes are compared with
conventional approaches (GCM-GOA, RPA, Lipkin-Nogami projection) for
rotational-vibrational motion and for particle number projection. The results
shows that the new schemes perform very well in all regimes of coupling.Comment: RevTex, 12 pages, 7 eps figure
QCD strings with spinning quarks
We construct a consistent action for a massive spinning quark on the end of a
QCD string that leads to pure Thomas precession of the quark's spin. The string
action is modified by the addition of Grassmann degrees of freedom to the
string such that the equations of motion for the quark spin follow from
boundary conditions, just as do those for the quark's position.Comment: REVTeX4, 10 pages, no figure
Influence of tunneling on electron screening in low energy nuclear reactions in laboratories
Using a semiclassical mean field theory, we show that the screening potential
exhibits a characteristic radial variation in the tunneling region in sharp
contrast to the assumption of the constant shift in all previous works. Also,
we show that the explicit treatment of the tunneling region gives a larger
screening energy than that in the conventional approach, which studies the time
evolution only in the classical region and estimates the screening energy from
the screening potential at the external classical turning point. This
modification becomes important if the electronic state is not a single
adiabatic state at the external turning point either by pre-tunneling
transitions of the electronic state or by the symmetry of the system even if
there is no essential change with the electronic state in the tunneling region.Comment: 3 figure
From Spatial Data to Synchronised Actions: the Network-centric Organisation of spatial decision support for risk and emergency management
A considerable amount of the required information in risk and emergency management is geographical, but this information does not always reach the right actors at the right time, so how can geographical information be organised in such a way that it supports risk and emergency management more effectively? The answer requires a conceptualisation of risk and emergency management practices resulting in the network-centric concept, which implies that those involved in risk and emergency management are connected and that they have the capability to share and access information. The concept was made operational through the development of an information system and the exchange of geographical information within the system was facilitated by the use of peer-to-peer networking in combination with a client server network. On the application level, the information was presented in both map and text forms to support the exchange of information between actors. This way of organising geographical information and technology leads to improved information and communication, better situational awareness and faster decision makin
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